Yonathan Melaku, 22, of Alexandria, Va., is being investigated in 2010 shootings at military buildings.

Federal prosecutors have charged the 22-year-old with two counts of discharging a firearm during a crime of violence and two counts of shooting at United States property, causing damage.

After Melaku was detained in Arlington National Cemetery last week by Fort Myer law enforcement officials, he was found to be in possession of ammonium nitrate, spent shell casings, and a notebook containing "Arabic statements referencing the Taliban, al Qaeda, Osama bin Laden, 'The Path to Jihad,' including 'defeat coalition and allies and America,'" according to an FBI affidavit released today.

The shootings in October and November targeted the Marine Corps museum in Quantico, Va., the Pentagon, and recruiting stations in Chantilly and Woodbridge, Va. At the time, FBI officials said they suspected the shooter had a gripe against the Marine Corps.

Now officials say they have linked Melaku to the crimes using ballistics tests on the shell casings in his backpack, according to the affidavit.

In Melaku's home, they also discovered a video of Melaku shooting at what appears to be the National Museum of the Marine Corps.

Melaku was detained early in the morning June 17 after he was spotted at Arlington National Cemetery after hours. He was carrying a backpack, which police initially feared contained bomb-making materials, though they later said the items were not explosive. When detained, authorities say he had a notebook with the words "al-Qaida" and "Taliban rules" written inside. Nearby, his car was parked just north of the Pentagon, in the bushes.

The investigation prompted major road closures near the Pentagon during the Friday morning rush.

Melaku has still not been charged in Friday's Pentagon incident. He is currently being held on unrelated grand larceny charges from a previous case in Leesburg, Va., from May.

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